Bleeding Brakes

[brucelotus26r]

How is the best way to bleed the brakes on my twin cam all shock. Any tricks
After resealing the trans, having the gas tanks clean & sealed and cleaning up & repainting the T part of the frame.
I took the car for a test drive and the brake pedal went 1/2 to the floor. I tried bleeding the brakes and they got worse so I rebuilt the master cylinder and bled them, better, but not as good as I was hoping for?

[tedtaylor]

Bruce, do you have the boosters in place or not?   I gave you that blog/article I wrote about the escapade I had bleeding and rebuilding my brake system.  Bleeding "should" be straightforward and typical of any car, but I used an air chuck on my master cylinder (low psi) to do the trick.
Did you use original configuration concerning the master cylinder, the push rod, original bore, etc.?

[BDA]

Do you still have your brake boosters? Obviously check for leaks everywhere. Boosters can leak internally. I assume you used a bottle with a tube that goes into some fluid so air can't be introduced from there when the pedal comes back. Also I assume you didn't over loosen the bleed screw. Pressure bleeders are very nice.


The sequence should be Pass. Front, Driver Front, Pass. Rear, Driver Rear (starting furthest away and going closer to the M/C).


I wouldn't think you'd need to, but as a last resort, you might try fluids designed for a more modern car. The ABS and traction controls require a thinner fluid and I would expect bubbles would be less persistent in a thinner fluid.

[tedtaylor]

.
The sequence should be Pass. Front, Driver Front, Pass. Rear, Driver Rear (starting furthest away and going closer to the M/C).

Forgive me but....   Your sequence above is not correct.   If you start furthest away from the MC, it would be Pass rear, Driver rear, Pass front, Driver front......yes?

[BDA]

On the stock TC, the fluid for both circuits goes to the back to the boosters and then to the calipers and wheel cylinders. That means the fronts are actually further from the M/C than the rears.

[tedtaylor]

I stand (sit) corrected!

[Grumblebuns]

Looking at the convoluted tubing run of the braking system, it's not hard to imagine why getting all of the air out of the system may be a bit difficult. The biggest culprit may be the loop up to the boosters (if you still have them) and back down to the PDWV. Power bleeding may be the way to go. Also make sure that the master cylinder has been bench bled before anything else.   

[BDA]

Ted, I have to sit when corrected. I can't stand that long or that many times! 


Joji, that was my assumption, too. I mounted my boosters behind the rear wheel well so my tubing and hose runs are more flat than the stock setup. I didn't have any trouble bleeding mine but I've heard some just have a horrible time.

[brucelotus26r]

The brakes are as original, rebuilt master ,new rear wheel cylinder, stock boosters and front calipers.
The shop manual say to bleed the side closest to the master first front ,then rear then front other side
rear other side.

[jbcollier]

Myself, I would either replace, overhaul or remove the nigh on 50 year old boosters.

[Bainford]

Myself, I would either replace, overhaul or remove the nigh on 50 year old boosters.

Me too, except I would just flat out remove them on anything used more often than a show car or museum piece.

[tedtaylor]

to each his own....
i was extremely happy/satisfied to rebuild and keep the boosters and original braking system intact.   excellent braking with little pedal effort.

[jbcollier]

Nothing wrong with keeping the boosters as long as they are either overhauled or replaced.

[brucelotus26r]

Where do you find the parts to rebuild the boosters?

[tedtaylor]

across the pond somewhere in England, or British Isles, or United Kingdom, or Britain, or one of those places!
I forget the vendor, but do an internet search for the parts and you'll come up with it.